U.S. patent application number 11/732433 was filed with the patent office on 2008-10-02 for electrical device with covering.
This patent application is currently assigned to Infineon Technologies AG. Invention is credited to Albert Auburger, Jean Schmitt, Terje Skog, Horst Theuss.
Application Number | 20080236278 11/732433 |
Document ID | / |
Family ID | 39792014 |
Filed Date | 2008-10-02 |
United States Patent
Application |
20080236278 |
Kind Code |
A1 |
Theuss; Horst ; et
al. |
October 2, 2008 |
Electrical device with covering
Abstract
The invention relates to a device comprising a sensor chip and a
structure housing the sensor chip. The structure is covered by a
mold compound and is fabricated from a ceramic or a glass
material.
Inventors: |
Theuss; Horst; (Wenzenbach,
DE) ; Auburger; Albert; (Karlstein, DE) ;
Skog; Terje; (Nykirke, NO) ; Schmitt; Jean;
(Zeitlarn, DE) |
Correspondence
Address: |
DICKE, BILLIG & CZAJA
FIFTH STREET TOWERS, 100 SOUTH FIFTH STREET, SUITE 2250
MINNEAPOLIS
MN
55402
US
|
Assignee: |
Infineon Technologies AG
Munchen
DE
|
Family ID: |
39792014 |
Appl. No.: |
11/732433 |
Filed: |
April 2, 2007 |
Current U.S.
Class: |
73/431 ;
29/825 |
Current CPC
Class: |
H01L 2924/181 20130101;
Y10T 29/49117 20150115; H01L 2224/48465 20130101; H01L 2224/48091
20130101; H01L 2924/1461 20130101; H01L 2224/48247 20130101; H01L
2224/48465 20130101; H01L 2924/181 20130101; H01L 2924/00014
20130101; H01L 2924/00 20130101; H01L 2924/00 20130101; H01L
2924/00 20130101; H01L 2924/00012 20130101; H01L 2224/48247
20130101; H01L 2224/48091 20130101; G01D 11/245 20130101; H01L
2924/1461 20130101; H01L 2224/48465 20130101; H01L 2224/48091
20130101 |
Class at
Publication: |
73/431 ;
29/825 |
International
Class: |
G01D 11/24 20060101
G01D011/24; H01R 43/00 20060101 H01R043/00 |
Claims
1. A device, comprising: a sensor chip; and a structure housing the
sensor chip and covered by a mold compound, wherein the structure
is fabricated from a ceramic or a glass material.
2. The device of claim 1, wherein the structure is mounted to a
carrier which is covered by the mold compound.
3. The device of claim 2, wherein the carrier is a leadframe.
4. The device of claim 2, wherein a main surface of the sensor chip
and a surface of the carrier are tilted by a tilt angle.
5. The device of claim 4, wherein the tilt angle of 90.degree..
6. The device of claim 1, wherein a contact element is applied to
an outer surface of the structure and the contact element is
electrically connected to the sensor chip.
7. The device of claim 6, wherein the contact element of the
structure is electrically connected to the carrier.
8. The device of claim 1, further comprising a semiconductor chip
covered by the mold compound.
9. The device of claim 8, further comprising a wire, an end of is
the wire being attached to the contact element of the structure and
another end of the wire being attached to the semiconductor
chip.
10. The device of claim 1, wherein the structure is sealed.
11. The device of claim 1, further comprising a plurality of leads
electrically connected to the sensor chip, wherein a respective end
point of each of the leads lies within a plane, and the main
surface of the sensor chip and the plane are tilted by a tilt
angle.
12. The device of claim 11, wherein each of the leads has a
respective bent.
13. The device of claim 11, wherein at least one of the leads has
two bents.
14. A method, comprising: placing a sensor chip in a structure
fabricated from at least one of a ceramic or a glass material; and
covering the structure with a mold compound.
15. The method of claim 14, wherein the structure is glued to a
carrier.
16. The method of claim 15, wherein the sensor chip is placed
within the structure, before the structure together with the sensor
chip is glued to the carrier.
17. The method of claim 14, wherein a semiconductor chip is
attached to the carrier and is covered with the mold compound,
before the structure together with the sensor chip is glued to the
carrier.
18. A device, comprising: a sensor chip; and a structure fully
encapsulating the sensor chip and covered by a mold compound,
wherein the thermal expansion coefficient of the structure lies in
a range from 0.310.sup.-6/K to 8.210.sup.-6/K.
19. The device of claim 18, wherein the structure is fabricated
from one or more of a ceramic, a glass, or a semiconductor
material.
20. The device of claim 18, wherein the structure is mounted to a
carrier which is covered by the mold compound.
21. The device of claim 20, wherein a main surface of the sensor
chip and a surface of the carrier are tilted by a tilt angle.
22. The device of claim 21, wherein the tilt angle is
90.degree..
23. The device of claim 18, wherein a contact element is applied to
an outer surface of the structure and the contact element is
electrically connected to the sensor chip.
24. The device of claim 18, further comprising a semiconductor chip
covered by the mold compound.
25. The device of claim 24, further comprising a wire, an end of is
the wire being attached to the contact element of the structure and
another end of the wire being attached to the semiconductor
chip.
26. A method, comprising: placing a sensor chip in a structure
having a thermal expansion coefficient in a range from
0.310.sup.-6/K to 8.210.sup.-6/K; sealing the structure by placing
a cover on the structure; and covering the structure with a mold
compound.
27. The method of claim 26, wherein the cover has a thermal
expansion coefficient in a range from 0.310.sup.-6/K to
8.210.sup.-6/K.
28. The method of claim 26, wherein the structure and the cover are
fabricated are fabricated from one or more of a ceramic, a glass or
a semiconductor material.
29. A device, comprising: a sensor chip; a semiconductor chip; a
ceramic or glass structure housing the sensor chip and having a
contact element; a carrier holding the semiconductor chip and the
ceramic or glass structure; and a wire, an end of which is attached
to the semiconductor chip and the other end of which is attached to
the contact element of the ceramic or glass structure.
Description
FIELD OF THE INVENTION
[0001] This invention relates to an electrical device in general
and more particularly to a sensor chip.
BACKGROUND OF THE INVENTION
[0002] Sensors are used in everyday life. Applications include
automobiles, machines, aerospace, medicine, industry and robotics.
Technological progress allows more and more sensors to be
manufactured on the microscopic scale included in semiconductor
chips.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0003] Aspects of the invention are made more evident by way of
example in the following detailed description of embodiments when
read in conjunction with the attached figures, wherein:
[0004] FIG. 1 shows a sectional side view of a device including a
sensor disposed in a structure;
[0005] FIG. 2 shows a sectional side view of a device including a
sensor fully covered by a structure;
[0006] FIG. 3 shows a sectional side view of a device including a
sensor and a semiconductor chip covered by a structure;
[0007] FIG. 4 shows a sectional side view of a device including a
sensor and a semiconductor chip in which the sensor is oriented
parallel with a surface of a carrier;
[0008] FIG. 5 shows a sectional side view of a device including a
sensor and a semiconductor chip in which a contact element is
disposed on an outer surface of a structure;
[0009] FIG. 6 shows a sectional side view of a device including a
sensor and a semiconductor chip in which a contact element is a
metallization later applied to a structure and bonded to the
semiconductor chip;
[0010] FIG. 7A shows a top plan view of a device including a
structure covering one or more devices;
[0011] FIG. 7B shows a perspective view of the device of FIG. 7A;
and
[0012] FIG. 8 shows fabrication steps to fabricate an embodiment of
the device.
DETAILED DESCRIPTION OF THE INVENTION
[0013] In the following embodiments of the invention are described
with reference to the drawings, wherein like reference numerals are
generally utilized to refer to like elements throughout, and
wherein the various structures are not necessarily drawn to scale.
In the following description, for purposes of explanation, numerous
specific details are set forth in order to provide a thorough
understanding of one or more aspects of embodiments of the
invention. It may be evident, however, to one skilled in the art
that one or more aspects of the embodiments of the invention may be
practiced with a lesser degree of these specific details. In other
instances, known structures and devices are shown in block diagram
form in order to facilitate describing one or more aspects of the
embodiments of the invention. The following description is
therefore not to be taken in a limiting sense, and the scope of the
invention is defined by the appended claims.
[0014] The devices described in the following contain sensor chips.
The specific embodiment of these sensor chips is not important in
this case. The sensor chips may contain electromechanical or
electrooptical functional elements. An example of an
electromechanical sensor is a microphone. Examples of
electrooptical sensors include photodiodes or diode lasers. The
sensor chips may also function fully electrically, for example, as
Hall Effect sensors. The sensor chips may be embodied as so-called
MEMS (Micro-Electro-Mechanical System), wherein micromechanical
movable structures such as, for example, bridges, membranes or reed
structures may be provided. Such sensor chips may be motion
sensors, which may be embodied as acceleration sensors (detecting
accelerations in different spatial directions) or rotation sensors.
Sensors of this type are also referred to as gyrosensors, roll-over
sensors, impact sensors, inertial sensors, etc. They are used for
example in the automotive industry for signal detection in ESP
(Electronic Stability Program) systems, ABS (Anti-lock Braking
Systems), airbags and the like. Usually such sensor chips are made
of a semiconductor material. However, the sensor chips are not
limited to be fabricated from a specific semiconductor material.
They may additionally contain non-conductive inorganic and/or
organic materials.
[0015] The described devices further contain a structure housing
the sensor chip. The structure may be made of a ceramic or a glass
material or combinations thereof. For example, the structure may be
fabricated using cofired ceramic multilayer structures, which may
contain (depending on the respective application) up to 40 or more
dielectric layers. Between adjacent layers electrically conductive
vias may be arranged. For example, the layers may contain
metallized traces or solder-filled vias, which are conventionally
made by thick-film metallization techniques including
screen-printing. Using such techniques, the structure housing the
sensor chip may then contain one or more contact elements providing
an electrical connection through the walls of the structure.
Including contact pads on the inner and outer surface of the
structure, an electrical connection between applications inside and
outside the structure can be established.
[0016] During the fabrication process, the multiple layers may be
joined together by a burnout process (at about 350.degree.
C.-600.degree. C.), which is followed by a firing process at
elevated temperatures (depending on the applied materials).
Conventionally used systems are low temperature cofired ceramic
(LTCC) or high temperature cofired ceramic (HTCC) multilayered
systems. HTCC systems may be fabricated by using aluminum
substrates; they are printed with molybdenum-manganese or tungsten
conducting traces and are fired at temperatures of about
1300.degree. C.-1800.degree. C. For LTCC systems various
glass-ceramic substrates are used, which are printed with gold,
silver or copper metallizations and are fired at temperatures of
about 600.degree. C.-1300.degree. C.
[0017] The structure housing the sensor chip may have a thermal
expansion coefficient similar or close to the thermal expansion
coefficient of the sensor chip. The structure may be of optional
shape and geometric form, it may particularly be sealed, for
example, by a cover also fabricated from a ceramic or glass
material. The structure housing the sensor chip and the cover
sealing the structure may also be fabricated from other materials
than ceramic or glass if these materials have thermal expansion
coefficients in the range from 0.310.sup.-6/K to 8.210.sup.-6/K
and, in particular, in the range from 4.010.sup.-6/K to
4.510.sup.-6/K.
[0018] Devices described herein further contain a mold compound
that partly or fully covers the structure housing the sensor chip.
Said mold compound may, for example, be made of a thermoplastic
resin or a thermosetting plastic (e.g. epoxy resin).
[0019] The devices may further comprise a semiconductor chip, which
may serve to control the functionality of the sensor chip or to
process signals that are sensed and/or generated by the sensor
chip. By way of example, in the case of the sensor chip being a
motion sensor, the deflection of a movable element comprised in the
sensor chip may be read piezoresistively or capacitively and may
then be processed by the semiconductor chip. The semiconductor chip
may be coupled to the sensor chip for the purpose of a
(bidirectional) data exchange. The semiconductor chip may, for
example, be embodied as an ASIC (Application Specific Integrated
Circuit).
[0020] FIG. 1 shows a sectional side view of a device 100 as a
first embodiment. The device 100 contains a sensor chip 1 housed in
a structure 2 made of a ceramic or a glass material. The structure
2 is covered by a mold compound 3. In the illustrated case, the
mold compound 3 only partly covers the structure 2 and does not
fully enclose it.
[0021] FIG. 2 shows a sectional side view of a device 200 as a
second embodiment. In comparison to the device 100 of FIG. 1, the
structure 2 of the device 200 fully encapsulates the sensor chip 1.
The structure 2 itself is covered by the mold compound 3. As for
the device 100, the structure 2 of the device 200 may be fabricated
from a ceramic or a glass material. Furthermore, the structure 2
may also be fabricated from a semiconductor material or any other
material having a thermal expansion coefficient in the range from
0.310.sup.-6/K to 8.210.sup.-6/K and, in particular, in the range
from 4.010.sup.-6/K to 4.510.sup.-6/K.
[0022] FIGS. 3 to 7 illustrate devices 300 to 700 representing
further implementations of the devices 100 and 200 described above.
The configurations of the devices 300 to 700, which are described
in the following, can therefore likewise be applied to the devices
100 and 200.
[0023] FIG. 3 shows a sectional side view of a device 300 as a
third embodiment. FIG. 3, as well as FIGS. 4-7, includes components
similar to those that are positioned and connected as shown, in one
implementation, in the steps depicted in FIG. 8 (although FIG. 8
literally shows the fabrication of a device 500 illustrated in FIG.
5). In comparison to the devices 100 and 200, the device 300
further comprises a semiconductor chip 4. The semiconductor chip 4
may, for example, be an ASIC that processes signals received from
the sensor chip 1. The semiconductor chip 4 may also control the
sensor chip 1. In the implementation of FIGS. 3-6, the sensor chip
1 is mounted in the structure 2, but the semiconductor chip 4 is
not. The semiconductor chip 4 and the structure 2 are both mounted
on a carrier 5, 6. In the case of the device 300, the carrier 5, 6
is implemented in form of a leadframe comprising at least one die
pad 5 and several leads 6 (or pins) surrounding the die pad 5. The
die pad 5 and the leads 6 may be fabricated from a metal, for
example, copper. Due to the chosen perspective, FIG. 3 only shows
two leads 6. In practice, the number of leads 6 for example depends
on the number of electrical contacts of the semiconductor chip 4
and/or the sensor chip 1. In the example of FIG. 3, the
semiconductor chip 4 is placed on the die pad 5, whereas the
structure 2 containing the sensor chip 1 is placed on some of the
leads 6. Alternatively, the structure 2 may be mounted on a
separate die pad. It is however understood that the carrier 5, 6 is
not restricted to embodiments as described above.
[0024] The structure 2, the semiconductor chip 4, and the die pad 5
are completely embedded in a mold compound 3, while portions of the
leads 6 protrude out of the mold compound 3. The portions of the
leads 6 that are not covered by the mold compound 3 may be bent as
illustrated in FIG. 3.
[0025] The structure 2 further comprises a contact element 7 having
contact pads on its inner and outer surface. Inside the structure
2, the contact element 7 is electrically coupled to the sensor chip
1 via a bond wire 8. In the embodiment shown in FIG. 3, the
structure 2 is placed on one of the leads 6 in such a manner that
the contact element 7 is in direct contact with one of the leads 6.
A good electrical contact between the contact element 7 and the
lead 6 may be assured by joining the contact element 7 with the
lead 6 using electrically conductive glue or by soldering the
contact element 7 with the lead 6.
[0026] The contact element 7 provides the possibility of an
electrical connection through the structure 2. The semiconductor
chip 4 is connected to several leads 6 via bond wires 8. One of
these bond wires 8 is connected to the lead 6 the contact element 7
is connected to. This bond wire 8 establishes an electrical
connection between the sensor chip 1 and the semiconductor chip 4.
Accordingly, a bidirectional data exchange between the sensor chip
1 and the semiconductor chip 4 is possible. It is to be noted that
the structure 2 may comprise more than one contact element 7 and
that the structure 2 (and thus the sensor chip 1) may be coupled to
the semiconductor chip 4 via several bond wires 8.
[0027] Further, it is to be noted that the sensor chip 1 and the
semiconductor chip 4 do not necessarily have to be wire bonded,
alternative types of mounting, such as flip-chip technology, may be
also used. Since the leads 6 protrude out of the mold compound 3,
they provide the possibility of the semiconductor chip 4 and the
sensor chip 1 being connected to an external system, for instance,
a circuit board.
[0028] One advantage of housing the sensor chip 1 in the structure
2 and covering the structure 2 with the mold compound 3 is that
stress effects on the sensor chip 1 are reduced. The reason is that
the thermal expansion coefficient of the structure 2 made of a
ceramic or glass material is similar to the thermal expansion
coefficient of the sensor chip 1. Accordingly, signals sensed
and/or generated by the sensor chip 1 and thus the overall
functionality of the device are less influenced by stress effects.
Due to their sensitivity, such influences on the sensing process
may particularly be considerable in the case of MEMS and Hall
Effect sensor chips.
[0029] It is to be noted that, in principle, any material may be
used for the fabrication of the structure 2 if the thermal
expansion coefficient of the chosen material matches the thermal
expansion coefficient of the sensor chip 1. In practice, the
thermal expansion coefficient of the structure 2 preferably lies in
the range from 0.310.sup.-6/K to 8.210.sup.-6/K. It is however
understood that the material composition and embodiment of the
structure 2 should be related to the respective case.
[0030] Housing the sensor chip 1 within the structure 2 further
reduces the risk of the bond wires 8, which are connected to the
sensor chip 1, being damaged. As can be seen in FIG. 3, due to the
complete enclosure of the sensor chip 1 and the bond wires 8 to the
sensor chip 1 by the structure 2, the mold compound 3 does not
contact the bond wires 8 and therefore no stress effects between
these components can occur. In case of a hermetically sealed
structure 2, the sensor chip 1 and the bond wires 8 housed in the
structure 2 are protected against any kind of undesired
environmental influences, such as intruding moisture.
[0031] The sensor chip 1 may be produced on a semiconductor wafer
with microstructures applied on the semiconductor wafer via planar
techniques. Therefore the sensing unit of the sensor chip 1, such
as movable elements in the case of a MEMS, is oriented within a
main surface of the sensor chip 1. For example, a micromechanical
movable membrane used for sensing of an acceleration is usually
oriented parallel to the main surface of the sensor chip 1.
[0032] In some cases, the physical value to be sensed by the sensor
chip 1 may depend on the spatial orientation of its main surface,
for example, when various spatial components of an acceleration are
to be detected. In the device 300, the structure 2 is mounted onto
the carrier 5, 6 in such a way that the spatial orientation of the
sensor chip 1, i.e. its main surface, supports the functional
requirements of the device 300. In FIG. 3, the main surface of the
sensor chip 1 and the surface of the carrier 5, 6 are tilted by a
tilt angle of about 90.degree.. (In FIG. 8, previously referenced,
the tilt angle of the sensor chip 1 to the surface of the carrier
5, 6 is 0.degree.; in FIG. 4, the sensor chip is mounted at a tilt
angle approximately 0.degree. as shown in FIG. 8.) It is however
understood that the main surface of the sensor chip 1 and the
surface of the carrier 5, 6 can be arranged with any tilt angle.
The tilt angle should be chosen in agreement with the desired
functionality of the device 300.
[0033] FIG. 4 shows a sectional side view of a device 400 as a
fourth embodiment. In contrast to the device 300, the structure 2
contained in the device 400 is placed on the carrier 5, 6 in such a
manner that the main surface of the sensor chip 1 is oriented
parallel to the surface of the carrier 5, 6. In case of the device
400, there is no tilt angle between the main surface of the sensor
chip 1 and the surface of the carrier 5, 6.
[0034] FIG. 5 shows a sectional side view of a device 500 as a
fifth embodiment. The difference between the devices 400 and 500
lies within the respective design of their contact elements 7. The
contact element 7 of the device 400 is in direct contact with one
of the leads 6, whereas the contact element 7 of the device 500 is
arranged on an outer surface of the structure 2, which does not
contact the carrier 5, 6. In this way, an electrical connection
between the contact element 7 and the semiconductor chip 4 can be
established via a bond wire 9, one end of which is attached to the
contact element 7 and the other end of which is attached to the
semiconductor chip 4. The bond wire 9 does not contact the carrier
5, 6. As a result, the additional connection between the contact
element 7 and the lead 6 (cf. FIG. 4) is omitted.
[0035] FIG. 6 shows a sectional side view of a device 600 as a
sixth embodiment. The device 600 differs from the device 300 in the
way the contact element 7 is designed. In FIG. 6, the contact
element 7 is a metallization layer which is applied to the
structure 2. Moreover, the contact element 7 is directly wire
bonded to the semiconductor chip 4.
[0036] FIG. 7A shows a top plan view of a device 700 as a seventh
embodiment. FIG. 7B shows another view of the device 700. The
internal structure of the device 700 may be the same as the
internal structure of one of the devices 300 to 600. Due to the
chosen perspective of FIG. 7A, the internal structure of the device
700, such as the sensor chip 1, the structure 2 and the
semiconductor chip 4, are not shown. The visible components of the
device 700 are the mold compound 3 and the portions of leads 6 and
10 protruding out of the mold compound 3. The device 700 has leads
not on four, but only on three sides of the device 700. As
indicated in FIG. 7A by an axis A 12, the leads 6 are bent by
90.degree.. Further, each of the two outer leads 10 are bent by
90.degree. in two places (cf. axes A 12, B 14, and C 16). The
bending of the leads 6 and 10 results in end points 11 of the leads
6 and 10, lying within a plane. This plane is the mounting plane of
the device 700, which can, for example, be used to mount the device
onto a circuit board. Since the main surface of the sensor chip 1
lies within the drawing plane of FIG. 7A, the main surface of the
sensor chip 1 and the mounting plane of the device 700 are tilted
by a tilt angle of 90.degree.. If, for some reason, the circuit
board is positioned so as not to be quite perpendicular to the
desired attitude of the device, the leads 6 may be bent at a
different angle to allow for orienting the device 700 at a desired
operating angle. For example, the leads 6 may be bent within
+45.degree. to -45.degree. of the circuit board to effect a desired
position of the device 700 regardless of the angular position of
the circuit board.
[0037] Besides a tilt angle between the main surface of the sensor
chip 1 and the surface of the carrier 5, 6 as shown in FIGS. 3 and
6, the bending of the leads 6 and 10 as proposed in FIGS. 7A and 7B
provides a further possibility to adjust the spatial orientation of
the sensor chip 1. It is understood that one or more of the leads 6
and 10 may have further bents. Specifically, the design of the
leads 6 and 10 may depend on the external application type as well
as on the desired functionality of the device 700.
[0038] FIG. 8 illustrates process steps of an exemplary fabrication
of the device 500. The components and properties of the device 500
were already described above. In a first step S1 20, a structure 2
made of a ceramic or glass material or any other material having a
thermal expansion coefficient in the range from 0.310.sup.-6/K to
8.210.sup.-6/K is provided. The structure 2 comprises at least one
contact element 7 which has contact pads inside and outside of the
structure 2. In a second step S2 22, a sensor chip 1 is mounted
onto the structure 2, for example by using a conventional die
attach method, such as gluing. Furthermore, the sensor chip 1 is
electrically connected to the contact element 7 via a bond wire 8.
In a third step S3 24, the structure 2 is closed and hermetically
sealed with a cover 12, which may be made of the same material as
the structure 2.
[0039] In a fourth step S4 26, a leadframe comprising a die pad 5
and leads 6 is provided. A semiconductor chip 4 is mounted on the
die pad 5 and is electrically connected to the leads 6 via bond
wires 8. The step S4 26 further comprises mounting the structure 2
onto the leadframe. This mounting process is not restricted to a
certain technique and may for example be carried out by gluing the
structure 2 to the leadframe. In a fifth step S5 28, the structure
2 and the semiconductor chip 4 are covered with a mold compound 3
in such a way that portions of the leads 6 protrude out of the mold
compound 3. Depending on the type of a possible external
application and the desired functionality of the device 500, the
leads 6 may be bent accordingly.
[0040] It is understood that all devices shown in FIGS. 1 to 7 may
be manufactured in a process similar to the one illustrated in FIG.
8. Moreover, the described process steps may be interchanged in any
reasonable way. For example, it is possible to perform the step S4
28 before the steps S1 20 to S3 26, i.e. the structure 2 may be
mounted onto the carrier 5, 6 first and the steps S1 20 to S3 24
may be performed afterwards with the structure 2 already attached
to the carrier 5, 6. It is also to be noted that further
fabrication steps may be added to the method illustrated in FIG.
8.
[0041] In addition, while a particular feature or aspect of an
embodiment of the invention may have been disclosed with respect to
only one of several implementations, such feature or aspect may be
combined with one or more other features or aspects of the other
implementations as may be desired and advantageous for any given or
particular application. Furthermore, to the extent that the terms
"include", "have", "with", or other variants thereof are used in
either the detailed description or the claims, such terms are
intended to be inclusive in a manner similar to the term
"comprise". The terms "coupled" and "connected", along with
derivatives may have been used. It should be understood that these
terms may have been used to indicate that two elements co-operate
or interact with each other regardless whether they are in direct
physical or electrical contact, or they are not in direct contact
with each other. Furthermore, it should be understood that
embodiments of the invention may be implemented in discrete
circuits, partially integrated circuits or fully integrated
circuits or programming means. Also, the term "exemplary" is merely
meant as an example, rather than the best or optimal. It is also to
be appreciated that features and/or elements depicted herein are
illustrated with particular dimensions relative to one another for
purposes of simplicity and ease of understanding, and that actual
dimensions may differ substantially from that illustrated
herein.
* * * * *